The rendering above shows the possibilities of placing wind turbines upon a multiple level structure, such as apartment buildings, office buildings, hotels, etc...
The V20 Quantum, for example, requires an estimated free space of 10m by 10m (100m²) free surface to be placed upon. This allows multiple turbines to be placed on a surface. The turbine can even be fitted with solar panels for added power generation.
Note that for existing structures calculations have to be made to ensure the load bearing capabilities of the roof support the extra load of the turbines.